Our global cover this week considers the impact of America’s poisonous politics on its mighty economy. In 1990 America accounted for about two-fifths of the GDP of the G7. Today it makes up half. But as they prepare to go to the polls in November, Republicans and Democrats have never mistrusted or disagreed with each other more. With the country becoming more partisan, both Kamala Harris and Donald Trump, the two presidential candidates, are focusing on policies that protect their own supporters, rather than expand the overall economic pie. America is not about to lose its economic dominance. But, sooner or later, rotten politics will start to exact a heavy price, and by then it will be hard to reverse course.